Overhearing this, Pilgrim said, "That blockhead — talking such rubbish, won't he frighten the Master?

Read what he is worried about. Not the demon, not the spell, not his own dismissal — that Bajie's doom-mongering will frighten the old man. After two beatings and two expulsions his first thought is still his master's peace of mind. 獃根 is "blockhead", a shade coarser than the usual 獃子. (諕 is xià, and 不 rises to bú before it.)

"Let old Sun go and take another look."

看看 — just have a look. He has promised not to strike, so he goes to look. The third reconnaissance, and technically within the letter of his word.

He hid the cudgel by his side, went forward, and facing the monster called out: "Old sir — where are you off to?

He hides the cudgel behind him first, which tells you what he expects to find. 老官兒 is a polite and faintly folksy way of addressing an old man, "old sir", carrying the small 兒 tag. The courtesy is entirely assumed: this is a man with a weapon behind his back asking a friendly question. (藏 is cáng, "to conceal"; 著 is zhe; 那裡 asks, so nǎ lǐ.)

"How is it you're walking the road, and reciting sutras too?"

The question looks innocent and is a probe. You are too infirm to manage the road, and yet you are chanting as you walk? It is the same move he made on the old woman's arithmetic: find the detail that does not fit, and lean on it.

The fiend, misreading its gauge and taking the Great Sage for some ordinary creature, answered: "Reverend, this old man's family has lived here for generations, all my life delighting in good works, feeding monks, reading scriptures and reciting the Buddha's name.

定盤星 is a fine piece of shop-floor vocabulary. On a steelyard balance it is the fixed mark that tells you where zero is; to 錯認了定盤星 is to misread your own scale, to take a wrong measure of something without knowing you have. She has weighed Wukong and got the answer badly wrong, treating him as 等閑的, just anybody. It is the mistake that kills her. (那 points, nà; 當 is dàng, "to regard as"; 長老 takes 長 as zhǎng; 佛 is Fó.)

"Fated to have no son, I got but one small daughter, and took in a son-in-law.

Notice how exactly this matches what the maiden said back in the first disguise: no son, one daughter, a son-in-law taken into the household. She is not improvising. She has held her story straight across three faces and several hours. (兒 here is the full noun ér, "a son"; 得 is the toneless complement marker.)

"This morning she took food down to the fields — set upon, I fear, by some tiger's maw.

虎口, the tiger's mouth, is the standard image for a violent end — and on this particular mountain it is entirely credible, since Wukong cleared the place of tigers in the chapter's second passage. She is explaining away the first body without ever mentioning a body.

"My old wife went first to look for her, and hasn't come back either.

And the second body, explained the same way. The wife went looking and did not come back. Two disguises retroactively converted into two missing persons.

"With no trace of either of them, this old man has come out on purpose to look.

So the story closes on itself: a family of three, two of them gone, the last of them out searching. There is nothing left in it for anyone to catch hold of.

"If it's true that their lives were cut short, there's no help for it — I'll gather up their bones and carry them home to be buried in the family plot."

The last touch is the one that would undo most listeners: if they are dead, I shall gather up their bones and bury them at home. 塋 (yíng) is the family burial plot. Grief, resignation and duty in a single sentence, and every word of it bait. There is an accident in it too, which she cannot see: bones gathered up on this mountain is exactly how the chapter ends, and they will be hers. (將 fronts the object; 中 is zhōng.)